This has 3/4" Female NPT threads on each side of the 90 degree elbow.  We use this with the 3/4" T-316 flexible braided stainless hose for the inlet to the pressure washer.  We then need a separate adapter to convert this to GHT to connect to the pressure washer inlet. 

Here would be your Flow Path if you're doing a stainless inlet hose setup: 

Hose Bib > 3/4" Female GHT Coupler > 3/4" Male GHT Plug > 3/4" Female GHT to 3/4" Female NPT > T316 Stainless Bucket Filler Hose > T-304 Stainless Elbow (THIS PART) > Brass 3/4" Male NPT to 3/4" Male GHT > 3/4" Female GHT Coupler > 3/4" Male GHT Plug > Pressure Washer Inlet